selenium: allow github-runner namespace ingress on 4444 (#26)

Unblocks CI jobs running in github-runner pods (e.g. FlowerCore.Print.Web
`help-screenshots`) from reaching selenium-hub. Previously the session
POST was DNAT'd to the hub pod IP then dropped at the Calico ingress
hook, surfacing as a 60s timeout against
http://selenium-hub.selenium.svc.cluster.local:4444 while the Selenium
UI showed 0/4 sessions.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/selenium/network-policy.yaml

@@ -24,7 +24,16 @@
 #     (10.0.57.16:5200), public internet 80/443 (excluding RFC1918), and
 #     fc-signage:5190 for the signage AAT lane.
 #   - Ingress: Traefik (4444 + 8089 ACME-solver-style), intra-pod,
-#     telephony / gitea / fc-system / fc-signage namespaces on 4444.
+#     telephony / gitea / fc-system / fc-signage / github-runner namespaces
+#     on 4444.
+#
+# 2026-05-25: added github-runner ingress on 4444 so CI jobs running in
+# self-hosted runner pods (e.g. FlowerCore.Print.Web `help-screenshots`)
+# can reach the grid. Without this allow, the session POST to
+# `selenium-hub.selenium.svc.cluster.local:4444` was DNAT'd to the hub
+# pod IP and then dropped at the Calico ingress hook — Selenium UI showed
+# 0/4 sessions while the .NET HTTP client timed out at 60s. Same family
+# as `feedback_netpol_dnat_backend_port`, wrong-source-namespace flavor.
 apiVersion: networking.k8s.io/v1
 kind: NetworkPolicy
 metadata:
@@ -203,6 +212,13 @@ spec:
     ports:
     - port: 4444
       protocol: TCP
+  - from:
+    - namespaceSelector:
+        matchLabels:
+          kubernetes.io/metadata.name: github-runner
+    ports:
+    - port: 4444
+      protocol: TCP
   podSelector: {}
   policyTypes:
   - Ingress